Yes, but the white supremacy ideology was and is not unique. There is a strain of thought in China about "Chinese supremacy". In Arab countries, large numbers of people believe in "Muslim supremacy", in that they believe that non-muslims are inferior, and it's justifiable to treat them badly.

Personally, I think people exaggerate the presence of white supremacy. We all unanimously agree as a culture that white supremacists are idiots. The US had a black president, the UK currently has a priminister of Indian origin and the mayor of London is from the middle-east.

Yes systemic racism exists, but its effects are exaggerated in mainstream culture. In the western world, people of all colours can become wildly successful. Asian Americans have proven that.